Answer:
Explanation:
We are asked to find the mass of a sample of metal. We are given temperatures, specific heat, and joules of heat, so we will use the following formula.
The heat added is 4500.0 Joules. The mass of the sample is unknown. The specific heat is 0.4494 Joules per gram degree Celsius. The difference in temperature is found by subtracting the initial temperature from the final temperature.
- ΔT= final temperature - initial temperature
The sample was heated <em>from </em> 58.8 degrees Celsius to 88.9 degrees Celsius.
- ΔT= 88.9 °C - 58.8 °C = 30.1 °C
Now we know three variables:
- Q= 4500.0 J
- c= 0.4494 J/g°C
- ΔT = 30.1 °C
Substitute these values into the formula.
Multiply on the right side of the equation. The units of degrees Celsius cancel.
We are solving for the mass, so we must isolate the variable m. It is being multiplied by 13.52694 Joules per gram. The inverse operation of multiplication is division, so we divide both sides by 13.52694 J/g
The units of Joules cancel.
The original measurements have 5,4, and 3 significant figures. Our answer must have the least number or 3. For the number we found, that is the ones place. The 6 in the tenth place tells us to round the 2 up to a 3.
The mass of the sample of metal is approximately <u>333 grams.</u>
The solid form of a substance is usually more dense than its
liquid and gaseous forms. Similarly the liquid form is usually more dense than
the gaseous form. Ice floating in water is an exception that breaks the general
density rule. So option “A” is the correct option in regards to the given
question. In case of ice formation, actually the density of water decreases by
about 9%. This is the main reason behind ice floating in water. Pure water has
the maximum density at 4 degree centigrade.
Answer:
Metals have one or two electrons in their outermost shell
C. 1-2
Explanation:
- Metals have low ionisation energy because they easily looses the outermost electrons
- They have only one- two electrons in the outer most shell.
- They loose these electron to form charged species called cation.
Answer:
Explanation:
To convert from moles to grams, the molar mass must be used.
1. Find Molar Mass
The compound is iron (III) chloride: FeCl₃
First, find the molar masses of the individual elements in the compound: iron (Fe) and chlorine (Cl).
There are 3 atoms of chlorine, denoted by the subscript after Cl. Multiply the molar mass of chlorine by 3 and add iron's molar mass.
- FeCl₃: 3(35.45 g/mol)+(55.84 g/mol)=162.19 g/mol
This number tells us the grams of FeCl₃ in 1 mole.
2. Calculate Moles
Use the number as a ratio.
Multiply by the given number of grams, 345.0.
Flip the fraction so the grams of FeCl₃ will cancel.
Divide.
3. Round
The original measurement of grams, 345.0, has 4 significant figures. We must round our answer to 4 sig figs.
For the answer we calculated, that is the thousandth place.
The 1 in the ten thousandth place tells us to leave the 7 in the thousandth place.
There are about <u>2.127 mole</u>s of iron (III) chloride in 345.0 grams.
Answer:
single displacement
Explanation:
the Fe was switched out with the C. they are the only ones that switched, making it a single displacement